End stop apparatus and methods

ABSTRACT

An adjustable end stop may selectively include one or more of the following elements: at least one guide member, a collapsible member, a movable assembly, a drive mechanism, and a position adjustment mechanism. The guide member may have the collapsible member and/or movable assembly attached thereto. The collapsible member may be configured to collapse when the end of the tubular member engages the collapsible member in a first direction and resist collapsing when the end of the tubular member engages the collapsible member in a second direction. The movable assembly may be movably attached to the at least one guide member, in which the movable assembly is configured to move along at least a portion of the length of the at least one guide rail. Further, the drive mechanism may be used to selectively position the collapsible member and/or movable assembly along the at least one guide member.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present Application claims priority to United Kingdom Patent Application Serial No. 0721435.6, filed on Nov. 1, 2007, and entitled “Drillpipe Stop.” The aforementioned priority application is hereby incorporated by reference in its entirety into the present Application.

BACKGROUND OF DISCLOSURE

1. Field of the Disclosure

Embodiments disclosed herein generally relate to methods and apparatus to support and/or move an end of a tubular member. More specifically, embodiments disclosed herein relate to apparatus that are used to support a tubular member during assembly, such as oilfield tubular members that are disposed downhole.

2. Background Art

In oilfield exploration and production operations, various oilfield tubulars are used to perform important tasks, including, but not limited to, drilling the wellbore and casing the drilled wellbore. For example, a long assembly of drill pipes, known in the industry as a drill string, may be used to rotate a drill bit at a distal end to create the wellbore. Furthermore, after a wellbore has been created, a casing string may be disposed downhole into the wellbore and cemented in place to stabilize, reinforce, or isolate (among other functions) portions of the wellbore. As such, strings of drill pipe and casing are often connected together, end-to-end by threaded connections, where a female “pin” member of a first tubular is configured to threadably engage a corresponding male “box” member of a second tubular. The process by which the threaded connections are screwed together is called “making-up” a threaded joint and the process by which the connections are disassembled is referred to “breaking-out” the threaded joint. As would be understood by one having ordinary skill, individual pieces (or “joints”) of oilfield tubulars come in a variety of diameters, configurations, and lengths.

Referring to FIG. 1, a perspective view is shown of a drilling rig 101 used to run tubular members 111 (e.g., casing, drill pipe, etc.) downhole into a wellbore. As shown, drilling rig 101 includes a frame structure known as a “derrick” 102 from which a traveling block 103 and an elevator 105 and/or a top drive (not shown) may be used to manipulate (e.g., raise, lower, rotate, hold, etc.) tubular members 111. As shown, traveling block 103 is a device that is located at or near the top of derrick 102, in which traveling block 103 may move up-and-down (i.e., vertically) to raise or lower tubular members 111. As shown, traveling block may be a simple “pulley-style” block and may have a hook 104 from which objects below (e.g., elevator 105) may be hung. Additionally, elevator 105 may also be coupled below traveling block 103 to selectively grab or release tubular members 111 as they are to be raised or lowered within and from derrick 102. Typically, elevator 105 includes movable gripping components (e.g., slips) movable between an open position and a closed position (shown in FIG. 1). In the closed position, the movable components form a load bearing ring (or shoulder) about or upon which tubular members 111 may bear and be lifted. In the open position, the movable components of elevator 105 may move away from one another to allow the tubular members 111 to be brought within or removed from elevator 105.

When assembling a string of tubular members 111 together, the tubular members 111 may be removed from a pipe rack 112 and pulled towards an access opening 121, for example, a v-door, within the derrick 102 of the drilling rig 101. The tubular members 111 may be loaded onto a pipe ramp 125 adjacent to the access opening 121, in which a rigidly mounted end stop 131 may abut the ends of the tubular members 111 to support the tubular members 111 up against access opening 121. An elevator, for example 105 in FIG. 1, or other lifting device (e.g., cable and/or winch) may then grasp an end of a tubular member 111 located within access opening 121 and may then raise the tubular member 111 up in derrick 102 so that it may be threadably connected to the remainder of a downhole string 115 of tubular members 111. The reverse process, or one substantially similar thereto, may be used, such as when removing tubular members from the drilling rig 101.

However, as tubular members 111 may vary in size and length as described above, if a selected tubular member 111 is too short (or long) for pipe ramp 125 (and rigidly mounted end stop 131) and therefore unable to reach access opening 121, drilling rig hands (i.e., crew members) may be required to place spacer blocks under a distal end of the tubular member 111 until elevator 105 is able to reach a proximal end of the tubular member 111 at access opening 121. Additionally, tubular members 111 may be cumbersome and/or difficult to handle because of their size, weight, and length such as when manually manipulating tubular members 111. Furthermore, the process of placing spacer blocks underneath a bottom of tubular members 111 consumes time, slowing production and therefore increasing drilling rig costs. Accordingly, there exists a need to increase the ability of the pipe rack (e.g., 112) and pipe ramp (e.g., 125) to prevent damage to tubular members when being assembled within a drilling rig and to be used with tubular members of varying lengths, sizes, and configurations, as may be common within the oilfield industry.

SUMMARY OF INVENTION

In a first aspect, embodiments disclosed herein relate to an adjustable end stop to support an end of a tubular member including at least one guide member, a collapsible member movably attached to the at least one guide member, and a drive mechanism to selectively position the collapsible member along the at least one guide member.

In another aspect, embodiments disclosed herein relate to an adjustable end stop to support an end of a tubular member including a movable abutment assembly comprising a collapsible member, and at least one guide member, wherein the abutment assembly is movably attached to the at least one guide member and configured to move along at least a portion of the at least one guide member.

In another aspect, embodiments disclosed herein related to an adjustable end stop to support an end of a tubular member including at least one guide member, a movable assembly attached to the at least one guide member, wherein the movable assembly is configured to move along at least a portion of the at least one guide member.

In another aspect, embodiments disclosed herein relate to an adjustable end stop to support an end of a tubular member including at least one guide member, a collapsible member attached to the at least one guide member, wherein the collapsible member is configured to collapse when the end of the tubular member engages the collapsible member in a first direction, and the collapsible member configured to resist collapsing when the end of the tubular member engages the collapsible member in a second direction.

In another aspect, embodiments disclosed herein relate to an adjustable end stop to support an end of a tubular member including a position adjustment mechanism, a movable assembly attached to the position adjustment mechanism, wherein the position adjustment mechanism is configured to displace the movable assembly, and the movable assembly configured to support the end of the tubular member.

In another aspect, embodiments disclosed herein relate to a method to make-up a first tubular with a second tubular including securing the first tubular with a drilling rig, adjusting an end stop to engage a first end of the second tubular, positioning the second tubular to the drilling rig, and making-up a threaded connection between the first and second tubulars.

In another aspect, embodiments disclosed herein relate to a method to assemble a plurality of tubulars to each other including positioning a first end of a first tubular adjacent to an end stop, adjusting the end stop to engage the first end of the first tubular, moving the first end of the first tubular with the end stop, positioning a second end of the first tubular adjacent to a drilling rig, and grasping the second end of the first tubular.

In another aspect, embodiments disclosed herein relate to an end stop to support an end of a tubular member including a collapsible member configured to operate between an open position and a closed position.

In another aspect, embodiments disclosed herein relate to a method to assemble a first tubular with a second tubular including traversing the second tubular across an end stop in a first direction, collapsing a collapsible member of the end stop with the second tubular in the first direction, and engaging the collapsible member to stop the second tubular from passing the end stop in a second direction.

Other aspects and advantages of the invention will be apparent from the following description and the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic view of a drilling rig.

FIGS. 2A and 2B show multiple views of an end stop in accordance with an embodiment of the present disclosure.

FIGS. 3A and 3B show multiple views of a movable member in accordance with an embodiment of the present disclosure.

FIG. 4 shows a cross-sectional view of the end stop shown in FIGS. 2A and 2B.

FIG. 5 shows a detail view of the end stop shown in FIGS. 2A and 2B.

FIGS. 6A and 6B shows multiple views of a securing mechanism in accordance with an embodiment of the present disclosure.

FIG. 7 is a schematic side view of an end stop in accordance with an embodiment of the present disclosure.

FIG. 8 shows a side view of a movable assembly in accordance with an embodiment of the present disclosure.

FIG. 9 is a schematic side view of an end stop in accordance with an embodiment of the present disclosure

DETAILED DESCRIPTION

Embodiments of the present disclosure will now be described in detail with reference to the accompanying Figures. Like elements in the various figures may be denoted by like reference numerals for consistency. Further, in the following detailed description of embodiments of the present disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the claimed subject matter. However, it will be apparent to one of ordinary skill in the art that the embodiments disclosed herein may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.

In one aspect, embodiments disclosed herein generally relate to an end stop used to support an end of a tubular member. As used herein, when supporting a tubular member with the end stop, the end stop may be able to sustain at least a portion of the weight of the tubular member and/or provide assistance when moving the tubular member. For example, the end stop may provide enough support to substantially carry the tubular member, or the end stop may provide enough support to only carry and/or move a fraction of the weight of the tubular member. Further, the end stop may provide support to a tubular member by asserting a force upon the tubular member. For example, the end stop may assert a force against the end of the tubular member to assist the tubular member when moving or sliding adjacent to the drilling rig. The end stop may include a movable assembly having a collapsible member and/or one or more sloped members. A collapsible member may be disposed between the sloped members, and/or a collapsible member may be configured to rotate between an open position and a closed position. A collapsible member may also be biased, such as towards the closed position.

The end stop may further include one or more guide members. In such an embodiment, the ends of the movable assembly may then be attached to the guide members. The movable assembly may move along the length of the guide members, or at least along a portion of the length of the guide members. For example, the attachment of the movable assembly to the guide members may define a plane, in which the movable assembly may then move along this plane with respect to the guide members. Further, in some embodiments, the movable assembly may only include a collapsible member, in which the collapsible member may be configured to be movable between an open position and a closed position.

A drive assembly may also be included with the end stop, such as having the drive assembly disposed within one or more of the guide members, in which the drive assembly may move the movable assembly along the guide members. For example, the drive mechanism may include a chain drive, in which the chain drive may include a chain disposed about sprocket gears within or adjacent to the guide members. A carrier may then be connected to this chain, and a lug disposed upon the movable assembly may attach to the carrier of the drive chain mechanism, thereby attaching the movable assembly to the guide member. This drive chain mechanism may be electrically powered, hydraulically powered, pneumatically powered, or the like, and a chain tension adjuster may be used in conjunction with the drive chain. Furthermore, the movable assembly may include bearings and rollers attached thereto to facilitate the movement of the movable assembly, and the guide members may be disposed upon a base plate for additional support.

Referring now to FIGS. 2A and 2B, an end stop assembly 201 in accordance with embodiments disclosed herein is shown. In FIG. 2A, a perspective view of end stop assembly 201 is shown and in FIG. 2B, an end view of end stop assembly 201 is shown. As shown, end stop assembly 201 includes a movable assembly 211 attached to a pair of guide members 231. While the guide members 231 are shown as guide rails in FIGS. 2A and 2B, it should be understood that the present disclosure contemplates the use of other structures as guide members. For example, guide members may be or include cables and/or other guiding apparatus without departing from the scope of the present disclosure. Further, while two guide members 231 are shown in FIG. 2A, it should be understood that the present disclosure contemplates structures having a single guide member 231 and structures having more than two guide members 231. As such, each end of movable assembly 211 may be attached to one of the guide members 231. The movable assembly 211 may be attached to the guide members 231 such that the movable assembly 211 may be displaced or repositioned along the length of the guide members 231 (discussed in more detail below).

Further, end stop assembly 201 may also include a base plate 291, wherein guide members 231 may be disposed upon (or attached to) base plate 291 or may be formed (i.e., integrally) with base plate 291. In the case where guide members 231 are attached to base plate 291, each guide member 231 may either be permanently or removably attached to the base plate 291. As such, guide members 231 may be attached using screws, bolts, or any other attachment device known in the art. Additionally, base plate 291 may be used to provide additional (structural, torsional, etc.) support to the end stop assembly 201.

Further, movable assembly 211 may include one or more collapsible members 213 and/or one or more sloped members 221. As shown in FIGS. 2A and 2B, the movable assembly 211 includes one collapsible member 213 that may be operable between an open (e.g., a “collapsed”) position and a closed (e.g., a “non-collapsed”) position. Further, the collapsible member 213 may (in select embodiments) be biased towards the closed position, such as by using a biasing member (e.g., a spring, a visco-elastic device, etc) to bias the collapsible member (discussed more below). Additionally, one having ordinary skill in the art will appreciate that the term “collapsible member” may apply to configurations other than those depicted in the Figures. In particular, while collapsible member 213 is shown as a structure analogous to a bottom, horizontally-hinged door with respect to a base plate 291, it should be understood that other configurations and mechanisms for collapsing member 213 may be used. For example, a single or a pair of vertically hinged doors (e.g., “French” doors), with respect to the base plate 291, may be used as a collapsible member in place of a single, downward collapsing member 213 depicted.

FIGS. 2A and 2B depict collapsible member 213 in the closed position. However, when a tubular member (e.g., 111 of FIG. 1) enters the end stop assembly 201 from side A (or is placed on top of collapsible member 213), the tubular member may slide across the collapsible member 213, opening the collapsible member 213. In select embodiments, collapsible member 213 may act as a mechanical check valve, meaning that if a tubular member (e.g., 111) is displaced across collapsible member 213, such as from side A, collapsible member 213 is configured to “give” and allow the tubular member to pass. However, when displaced in the opposite direction, collapsible member 213 may “lock” and disallow a tubular member to traverse across stop assembly 201 in the reverse direction. However, in alternative embodiments, collapsible member 213 may be bi-directional, allowing a tubular member to traverse across stop assembly 201 in either direction, but may be locked at any time, either manually or automatically to prevent tubular members from traversing across stop assembly 201. Further, a controller and/or a sensor (both not shown), may be included and/or attached to collapsible member 213 and/or end stop 201. The sensor may be used to detect the presence of a tubular, and the controller may be used to operate collapsible member 213 and/or other operable elements of end stop 201. Furthermore, sloped members 221, or the like, may assist in “guiding” the trailing end of the tubular member into alignment with collapsible member 213.

In some embodiments, opening the collapsible member 213 involves rotating collapsible member 213 by about 90 degrees. The collapsible member 213 may then lie substantially flat, such as against the base plate 291, in which this will allow the tubular member to slide through end stop 201. After the tubular member slides through the movable assembly 211, the collapsible member 213 may then move from the open position back towards the closed position. For example, because the collapsible member 213 may be biased toward the closed position, the collapsible member 213 may move back to the closed position automatically without any assistance. Further, in other embodiments, the collapsible member 213 may include one or more actuators operatively attached thereto and configured to open or close collapsible member 213 using, for example, pneumatic, hydraulic, electrical, and/or mechanical power. In such embodiments, the one or more actuators may be remotely controlled to move the collapsible member 213 between the open and closed positions. In one embodiment, after the tubular member then passes through the movable assembly 211, the tubular member may then be allowed to rest against the movable assembly 211 after the collapsible member 213 has moved back to the closed position.

End stop assembly 201 may be placed upon a pipe ramp to facilitate the movement of tubular members, such as when assembling or disassembling a drillstring or casing string on a drilling rig. For example, as discussed above in reference to FIG. 1, when assembling tubular members through a v-door using a pipe ramp, some of the tubular members may be too short or not long enough to extend an appropriate length through the v-door to be grasped by the elevator for assembly. However, when using the end stop assembly 201 in accordance with one embodiment of the present disclosure, the tubular members may slide through the collapsible member 213 of the movable assembly 211, and then rest upon the movable assembly 211. If the tubular member is of such a length to inadequately be positioned (e.g., extend) to the v-door, the movable assembly 211 may then be actuated and moved along the guide members 231 until the tubular member is properly positioned. Therefore, the movement of the movable assembly 211 may push the tubular member down or up to, and possibly through, the v-door of the drilling rig (or another desired location), for example, thereby enabling the tubular member to be more easily grasped for assembly.

Referring now to FIGS. 3A and 38, perspective views of a movable assembly 311 in accordance with embodiments of the present disclosure are shown. More particularly, in FIG. 3A, a perspective view of the back side of the movable assembly 311 is shown, and in FIG. 3B, a perspective view of the front side of the movable assembly 311 is shown. Similar to movable assembly 211 described above, movable assembly 311 may include a collapsible member 313 rotatable between an open position and a closed position and one or more sloped members 321. In FIGS. 3A and 3B, the collapsible member 313 is shown in the closed position. As shown, collapsible member 313 may be attached to the sloped members 321 by a hinge 315. In FIGS. 3A and 3B, the hinge 315 is shown disposed at a lower end of collapsible member 313 so that it may be rotatable about the hinge 315 between open and closed positions. However, in other embodiments, the hinge 315 may be disposed at a side end of collapsible member 313 so that it is rotatable about a side surface thereof between open and closed positions. In one embodiment, hinge 315 may be attached to one of the sloped members 321.

Further, as discussed above, collapsible member 313 may be biased towards the closed position. To bias the collapsible member 313 towards the closed position, the movable assembly 311 may include a biasing mechanism. As shown, movable assembly 311 may include a spring 317 disposed within sloped member 321 and attached to the collapsible member 313 to produce a biasing force urging collapsible member 313 into the closed position.

Although a single spring is shown in FIG. 3A, those having ordinary skill will appreciate that other mechanisms for biasing collapsible member 313 may be used without departing from the scope of the present disclosure. For example, spring (e.g., 317) may be disposed within both sloped members 321 to produce a biasing force upon collapsible member 313. Alternatively, in other embodiments, hinge 315 attached between collapsible member 313 and sloped members 321 may be self-biasing so that the hinge itself may bias collapsible member 313 towards the closed position.

As discussed above, movable assembly 311 may include one or more sloped members 321. Sloped members 321 may be formed such that an upper surface 323 of the sloped members 321 slopes towards collapsible member 313. As such, sloped members 321 may have a varying height, in which the height of an end of sloped member 321 adjacent to collapsible member 313 is lower than the height of an end of sloped member 321 distant from collapsible member 313. This variation in height of sloped member 321 may desirably create sloped upper surface 323 for sloped member 321.

By having one or more sloped members 321 included within movable assembly 311, sloped members 321 may guide tubular members entering movable assembly 311 toward collapsible member 313. For example, when using the end stop to support an end of a tubular member, the tubular member may slide into the end stop and adjacent the movable assembly. If the tubular member is optimally aligned with collapsible member 313 of the movable assembly 311, the tubular member may then slide up to and engage the collapsible member 313. However, if the tubular member is not optimally aligned with movable assembly 311, sloped members 321 may urge the tubular member (i.e., centralize) towards collapsible member 313 when engaging the movable assembly 311. As such, sloped (or other urging) members 321 may be used to facilitate the movement of the tubular members within an end stop (e.g., 201) and therefore may prevent damage to tubular members.

In select embodiments, sloped members 321 may have a generally triangular shape, as shown in FIGS. 3A and 3B. However, those having ordinary skill will appreciate the shape of the sloped members 321 may be any shape or style known in the art to facilitate the movement of tubular members within movable assembly 311. Further, as shown in FIGS. 3A and 3B, sloped members 321 may also be partially or substantially hollow, such as to conserve weight, although in other embodiments, sloped members 321 may be partially or substantially filled to provide additional structural support for sloped members 323.

Further, as shown in FIGS. 3A and 3B, the collapsible member 313 may be disposed between the sloped members 321. However, those having ordinary skill in the art will appreciate that any arrangement of collapsible member 311 and sloped members 321 may be used without departing from the scope of the present disclosure. For example, in alternative embodiments, a single sloped member may be used within a movable assembly (e.g., 211, 311) in which the single sloped member is configured to urge tubular members towards a collapsible member. In other embodiments, the movable assembly may not contain any sloped members at all.

Referring still to FIGS. 3A and 3B, movable assembly 311 may include one or more rollers 325 and/or one or more bearings 327. Rollers 325 may be used to facilitate the movement of movable assembly 311 by reducing frictional forces that may be produced between a lower surface of movable assembly 311 and a base plate (e.g., 291 of FIGS. 2A and 2B) or another base surface. As such, rollers 325 may be disposed at one or both ends of movable assembly 311 and/or may be disposed internally within movable assembly 311. In select embodiments, rollers 325 may be disposed within sloped members 321 and may extend from a bottom surface of sloped members 321.

Similarly, bearings 327 may be used to facilitate the movement of movable assembly 311 by reducing frictional forces that may be produced between side surfaces of movable assembly 311 and guide members (e.g., 231 of FIGS. 2A and 2B). As such, bearings 327 may be disposed at one or both ends of the movable assembly 311, in which the bearings 327 may then engage a surface of guide members of an end stop assembly. Furthermore, as shown in FIGS. 3A and 3B, movable assembly 311 may include one or more lugs 329 to facilitate movement, installation, removal, maintenance, and adjustment of movable assembly within an end stop assembly (e.g., 201 of FIGS. 2A and 2B).

Referring now to FIG. 4, a cross-sectional view of the end stop assembly 201 of FIGS. 2A and 2B taken across line 4-4 of FIG. 2B is shown. As described above, movable assembly 211 may be attached to guide members 231 such that movable assembly 211 may traverse along a length of guide members 231. As such, guide members 231 may include a drive mechanism 241 to provide powered movement of the movable assembly 211, such as along guide members 231. As shown, a drive mechanism 241 may be disposed within each of the guide members 231. However, those having ordinary skill will appreciate that one or more drive mechanisms may be disposed on an outer surface of the one or more guide members 231, or that end stop 211 may include a single drive mechanism to move movable assembly 211.

Drive mechanism 241 depicted in FIG. 4 is a chain-drive mechanism. However, those having ordinary skill will appreciate that actuators (e.g., linear) or other drive mechanisms, including, but not limited to, belt-drive, screw-drive, pneumatic-drive, and hydraulic-drive power systems may be used without departing from the scope of the present disclosure. As depicted, drive mechanism 241 may include a plurality of sprocket gears 243, a carrier 245, and a chain (not visible). As shown, sprocket gears 243 may be disposed at opposite ends of guide member 231 from each other with the chain extending therebetween.

Carrier 245 may then be operatively connected to the chain of drive mechanism 241 (between sprocket gear 243), such that carrier 245 may reciprocate between sprocket gears 243 as they rotate (with chain) in either direction. As such, when sprocket gears 243 of drive mechanism 241 rotate, their rotation will similarly rotate the chain extending therebetween. As the chain then moves, carrier 245, which is connected to the chain, will also move. Thus, the rotational movement of sprocket gears 243 may be transferred into generally linear movement of movable assembly 211 connected to carrier 245. For example, when the gears 243 rotate in one direction, carrier 245 (and attached movable assembly 211) may then move in a first direction along the length of guide member 231. As the gears 243 then rotate in the opposite direction, carrier 245 (and attached movable assembly 211) may then move in an opposite direction along the length of guide member 231.

As suggested above, movable assembly 211 may be connected to carrier 245 of drive mechanism 241. For example, referring briefly to FIGS. 3A and 3B, lugs 329 of movable assembly 311 may be connected to carrier 245, in which the movement of the carrier 245 along the length of the guide member 231 may be translated to the movable assembly 211. However, those having ordinary skill will appreciate that other mechanisms for attaching movable assembly 211 (or 311) to carrier 245 (or drive mechanism 241) may be used without departing from the scope of the present disclosure.

Referring again to FIG. 4, drive mechanism 241 may further include a chain drive adjuster 247. Chain drive adjuster 247 may be used to adjust a tension of the chain of drive mechanism 241 to ensure proper operation of drive mechanism 241. Chain drive adjuster may be used to adjust a distance between sprocket gears 243 of drive mechanism 241, thereby increasing or decreasing the tension across the chain of the drive mechanism 241.

Referring now to FIG. 5, a detail view of the end stop assembly 201 taken from detail scope 5 of FIG. 2A is shown. To facilitate the movement of the movable assembly 211 of the end stop assembly 201, the end stop assembly 201 may include one or more actuators, such as motors 249. A motor 249 may be operatively connected to one or more of drive mechanisms 241 of end stop assembly 201. For example, if two drive mechanisms 241 are used to traverse movable assembly 211, then one or more motors 249 may be connected to one or both of drive mechanisms 241 to rotate selected sprocket gears 243. In select embodiments, motors 249 are electrically powered, but it should be understood that other types of motors (e.g., pneumatic, hydraulic) may be used without departing from the scope of the present disclosure.

Motors 249 may be operatively connected to drive mechanism 241 to provide power to drive mechanism 241. For example, in select embodiments, motor 249 may be connected to one of sprocket gears 243 of drive mechanism 241. Motor 249 may then rotate a gear 243 which will translate into movement of movable assembly 211 along the length of the guide member 231. However, those having ordinary skill will appreciate that other methods may be used to power the drive mechanism.

Further, referring now to FIGS. 5, 6A, and 6B together, end stop assembly 201 may include one or more securing mechanisms 251 to secure end stop assembly 201 to a drilling rig, (e.g., floor) or a pipe rack or other associated structure. As shown, the securing mechanism 251 may include an arm 253 configured to fit within a boss member 255. As such, arm 253 may be removably or permanently connected to boss member 255. For example, as shown particularly in FIG. 6B, arm 253 may threadably engage with boss member 255, such as by having a bolt 258 extending through an end of arm 253 and into boss member 255.

When connected with boss member 255, the end of arm 253 of securing mechanism 251 may extend downward, such as with respect to and past a lower surface of movable member 211 and guide members 231. For example, as shown FIG. 2B, arm 253 of securing mechanism 251 may extend past a lower surface (e.g., below base plate 291) of movable member 211 and guide members 231. As such, arm 253 of securing mechanism 251 may extend into a surface of the drilling rig floor or the pipe rack to secure end stop assembly 201 thereto. For example, arm 253 may have an aperture 257 formed therein, in which an attachment device, such as a bolt, screw, nail, or clasp, may be disposed within the aperture 257 to secure end stop assembly 201 and prevent movement thereof.

In select embodiments, boss member 255 of securing mechanism 251 may be movably connected to end stop assembly 201. For example, as shown in FIG. 5, boss member 255 of securing mechanism 251 may be attached to a surface of guide member 231 such that boss member 255 is able to move along a side of guide member 231. As such, securing mechanism 251 may be adjusted relative to remainder of end stop assembly 210 to facilitate alignment and positioning of end stop assembly 201 on the drilling rig floor or the pipe rack.

Referring now to FIG. 7, an end stop assembly 701 is shown (schematically and not to scale) supporting a tubular member 111 while positioned upon a pipe ramp 125. As such, end stop assembly 701 may abut an end of tubular member 111 when tubular member 111 is loaded upon pipe ramp 125 for assembly of a string of downhole tubular members (e.g., a drillstring or a casing string). As shown, end stop assembly 701 may include a position adjustment mechanism 771 attached and/or operatively coupled thereto. As depicted in FIG. 7, position adjustment mechanism 771 may include a lift mechanism (e.g., a scissor-jack, a hydraulic elevator, a ball screw lifting mechanism, etc.), in which position adjustment mechanism 771 may be disposed to end stop assembly 701 (e.g., upon a bottom surface thereof). Specifically, in certain embodiments, position adjustment mechanism 771 may be disposed upon a bottom surface of base plate 791 of end stop assembly 701. Additionally, in certain embodiments, an extension panel 772 may be hingedly (or otherwise) connected to base plate 791 at 773, Extension panel 772 may allow tubular member 111 to smoothly transfer from end stop assembly 701 to pipe ramp 125 when raised from the drilling rig.

Further, end stop assembly 701 may include movable assembly 711, in which movable assembly 711 may be able to move along length of base plate 791. However, while movable assembly 711 is shown as included with end stop assembly 701, it should be understood that the present disclosure contemplates structures having an end stop assembly without a movable assembly 711. As such, end stop assembly 701 may instead include position adjustment mechanism 771, in which position adjustment mechanism 771 may adjust the position of end stop assembly 701.

Further, while position adjustment mechanism 771 is shown as having a scissor lift mechanism to adjust the height of end stop assembly 701, it should be understood that the present disclosure contemplates structures having a position adjustment mechanism configured to adjust the position of end stop assembly 701 in more than one direction, such as by laterally and/or vertically. As such, position adjustment mechanism 771 may be configured to adjust the position of end stop assembly 701 in one or more of the directions in a Cartesian coordinate system (x-direction, y-direction, and z-direction).

Furthermore, in other embodiments, the position adjustment mechanism may include one or more actuators to adjust the position of the end stop assembly. As schematically shown (i.e., not to scale) in FIG. 9, end stop assembly 901 includes two actuators to adjust the position of end stop assembly 901. Specifically, in this embodiment, position adjustment mechanism 971 schematically illustrates a fluid actuator 971A and a screw drive actuator 971B, although one type of actuator may be used. Fluid actuator 971A may be disposed at one end of base plate 991 of end stop assembly 901, and screw drive actuator 971B may be disposed at another end of base plate 991 of end stop assembly 901. As with FIG. 7, an extension panel 992 may be hingedly (or otherwise) connected to base plate 991 at 993. Actuators may then move together and/or independently of each other when adjusting the position of end stop assembly 901. While actuators 971A, 971B are shown as disposed at the ends of base plate 991 of end stop assembly 901, it should be understood that the present disclosure contemplates structures having other locations and arrangements to adjust the position of end stop assembly 901. For example, in some embodiments, one or more actuators may be attached to a top side of base plate 991, and/or one or more actuators may be attached to movable assembly 911.

Referring now to FIG. 8, a side view of a movable assembly 811 is shown. In this embodiment, movable assembly 811 may have a slot 819 formed therein, in which slot 819 may be formed such as to receive the end of a tubular member. As such, movable assembly 811 may have a collapsible member attached thereto, or may be formed without the need of a collapsible member (as shown in FIG. 8). As above, movable assembly 811 may then be attached to one or more guide members, in which movable assembly 811 may be configured to move along the length of the guide members and/or support the end of the tubular member.

Embodiments disclosed herein may provide for one or more of the following advantages. First, embodiments disclosed herein may provide for an end stop that prevents or minimizes damage to tubular members being grasped for assembly from a pipe rack. For example, when a tubular member engages the movable assembly of the present disclosure, the movable assembly will allow the tubular member to pass therethrough without having to pick up and move or drag the pipe over the end stop. Further, embodiments disclosed herein may provide for an end stop that is movable to facilitate the assembly of tubular members. For example, when using an end stop in accordance with the present disclosure, the movable member of the end stop may be able to move a tubular member resting thereupon, thereby allowing a user to control the location of the tubular member for grasping and assembly.

Furthermore, it should be understood by those having ordinary skill that the present disclosure shall not be limited to specific examples depicted in the Figures and described in the specification. As such, various mechanisms to adjust the effective length of a tubular member in an oilfield drilling rig (e.g., 101 of FIG. 1) may be used without departing from the scope of the present disclosure. While the present disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as described herein. Accordingly, the scope of the invention should be limited only by the attached claims. 

1. An adjustable end stop to support an end of a tubular member, comprising: at least one guide member; a collapsible member movably attached to the at least one guide member; and a drive mechanism to selectively position the collapsible member along the at least one guide member.
 2. The adjustable end stop of claim 1, further comprising at least one sloped member adjacent to the collapsible member, wherein the at least one sloped member is configured to align the end of the tubular member with the collapsible member as it engages the collapsible member in the first direction.
 3. The adjustable end stop of claim 1, wherein the at least one guide member is connected to a base plate, wherein the collapsible member is configured to move in a direction along the base plate.
 4. The adjustable end stop of claim 1, further comprising a securing mechanism configured to secure the guide member relative to a lifting component of a drilling rig.
 5. The adjustable end stop of claim 4, wherein the lifting component comprises at least one of a pipe rack, a v-door, a rig floor, an access opening, a derrick, an elevator, and a traveling block.
 6. The adjustable end stop of claim 1, wherein the collapsible member is configured to collapse when the end of the tubular member engages the collapsible member in a first direction and resist collapsing when the end of the tubular member engages the collapsible member in a second direction.
 7. The adjustable end stop of claim 6, wherein the collapsible member is biased towards a non-collapsed position.
 8. An adjustable end stop to support an end of a tubular member, comprising: a movable abutment assembly comprising a collapsible member; and at least one guide member, wherein the abutment assembly is movably attached to the at least one guide member and configured to move along at least a portion of the at least one guide member.
 9. The adjustable end stop of claim 8, further comprising at least one sloped member comprising an upper surface that slopes toward the collapsible member.
 10. The adjustable end stop of claim 8, wherein the collapsible member is configured to operate between an open position and a closed position.
 11. The adjustable end stop of claim 10, wherein the collapsible member comprises an actuator to operate between the open position and the closed position.
 12. The adjustable end stop of claim 10, wherein the collapsible member is biased toward the closed position.
 13. The adjustable end stop of claim 8, wherein: the collapsible member is configured to collapse when the end of the tubular member engages the collapsible member in a first direction; and the collapsible member is configured to resist collapsing when the end of the tubular member engages the collapsible member in a second direction.
 14. The adjustable end stop of claim 8, further comprising a drive mechanism to selectively position the collapsible member along the portion of the length of the at least one guide member.
 15. An adjustable end stop to support an end of a tubular member, comprising: at least one guide member; a movable assembly attached to the at least one guide member; wherein the movable assembly is configured to move along at least a portion of the at least one guide member.
 16. The adjustable end stop of claim 15, further comprising: a drive mechanism to selectively position the collapsible member along a length of at least one guide member.
 17. The adjustable end stop of claim 15, further comprising: a collapsible member movably attached to the movable assembly; wherein the collapsible member is configured to operate between an open position and a closed position.
 18. An adjustable end stop to support an end of a tubular member, comprising: at least one guide member; a collapsible member attached to the at least one guide member; the collapsible member configured to collapse when the end of the tubular member engages the collapsible member in a first direction; and the collapsible member configured to resist collapsing when the end of the tubular member engages the collapsible member in a second direction.
 19. The adjustable end stop of claim 18, wherein the collapsible member is movably attached to the at least one guide member, the adjustable end stop further comprising: a drive mechanism to selectively position the collapsible member along a length of the at least one guide member.
 20. An adjustable end stop to support an end of a tubular member, comprising: a position adjustment mechanism; a movable assembly attached to the position adjustment mechanism; the position adjustment mechanism configured to displace the movable assembly; and the movable assembly configured to support the end of the tubular member.
 21. The adjustable end stop of claim 20, wherein the position adjustment member is configured to move the movable assembly in at least one of a lateral direction and a vertical direction.
 22. The adjustable end stop of claim 20, wherein the movable assembly is movably attached to the at least one guide member, the adjustable end stop further comprising: a drive mechanism to selectively position the movable assembly along a length of the at least one guide member.
 23. The adjustable end stop of claim 20, further comprising: a collapsible member movably attached to the movable assembly; wherein the collapsible member is configured to operate between an open position and a closed position.
 24. A method to make-up a first tubular with a second tubular, the method comprising: securing the first tubular with a drilling rig; adjusting an end stop to engage a first end of the second tubular; positioning the second tubular to the drilling rig; and making-up a threaded connection between the first and second tubulars.
 25. The method of claim 24, further comprising: grasping a second end of the second tubular with an elevator; and raising the second tubular above the first tubular with the elevator.
 26. The method of claim 24, further comprising; positioning the second tubular on a pipe rack comprising the end stop; retracting the end stop to a position behind the first end of the second tubular; and extending the end stop to raise the second tubular up a v-door of the drilling rig.
 27. The method of claim 24, wherein the end stop comprises a collapsible member.
 28. The method of claim 27, wherein the end stop further comprises a controller and a sensor, wherein the adjusting the end stop to engage the first end of the second tubular comprises: detecting a presence of a tubular member with the sensor; and moving the collapsible member of the end stop assembly with the controller.
 29. The method of claim 24, wherein the end stop comprises a drive mechanism to adjust the end stop to engage the first end of the second tubular.
 30. A method to assemble a plurality of tubulars to each other, the method comprising: positioning a first end of a first tubular adjacent to an end stop; adjusting the end stop to engage the first end of the first tubular; moving the first end of the first tubular with the end stop; positioning a second end of the first tubular adjacent to a drilling rig; and grasping the second end of the first tubular.
 31. The method of claim 30, wherein the end stop comprises a collapsible member movably attached thereto, wherein the collapsible member is configured to operate between an open position and a closed position.
 32. The method of claim 30, wherein the end stop comprises a movable assembly movably attached to a guide member, wherein the movable assembly moves the first end of the first tubular.
 33. The method of claim 30, wherein the end stop comprises a position adjustment mechanism to move the first end of the first tubular.
 34. The method of claim 30, wherein the second end of the first tubular is positioned at a desired location on the drilling rig.
 35. An end stop to support an end of a tubular member, comprising: a collapsible member configured to operate between an open position and a closed position.
 36. The end stop of claim 35, wherein the collapsible member is configured to collapse when the end of the tubular member engages the collapsible member in a first direction and resist collapsing when the end of the tubular member engages the collapsible member in a second direction.
 37. The end stop of claim 35, further comprising at least one guide member.
 38. The end stop of claim 35, further comprising a position adjustment mechanism, the position adjustment mechanism configured to displace the end stop.
 39. A method to assemble a first tubular with a second tubular, the method comprising: traversing the second tubular across an end stop in a first direction; collapsing a collapsible member of the end stop with the second tubular in the first direction; and engaging the collapsible member to stop the second tubular from passing the end stop in a second direction.
 40. The method of claim 39, further comprising: securing the first tubular with a drilling rig; grasping a second end of the second tubular with an elevator; raising the second tubular above the first tubular with the elevator; and making-up a threaded connection between the first and the second tubulars.
 41. The method of claim 39, further comprising moving the second tubular with a positioning system of the end stop.
 42. The method of claim 39, further comprising guiding the second tubular across the collapsible member with at least one guide member. 